Wash the dandelion greens and set them in a large bowl of ice water. Let them sit at least 15 minutes before proceeding. Move them to a colander to drain.

Heat the olive oil in a large saute pan over medium-high heat. Cook the onions until they're soft, but not browned. Add the garlic and chile and cook another minute.

Move the dandelion greens to the pan, where they will pop and spatter a bit. Stir-fry them until they all wilt, then sprinkle salt over everything. Cook another minute or three -- the older the greens are, the longer you will need to cook them -- then turn off the heat and add the black pepper, a little nice olive oil, and some lemon juice. Serve at once.